398238761 has 2 divisors, whose sum is σ = 398238762. Its totient is φ = 398238760.

The previous prime is 398238697. The next prime is 398238779. The reversal of 398238761 is 167832893.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 217739536 + 180499225 = 14756^2 + 13435^2 .

It is a cyclic number.

It is not a de Polignac number, because 398238761 - 2⁶ = 398238697 is a prime.

It is a super-2 number, since 2×398238761² = 317188221525630242, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (398238791) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 199119380 + 199119381.

It is an arithmetic number, because the mean of its divisors is an integer number (199119381).

Almost surely, 2^398238761 is an apocalyptic number.

It is an amenable number.

398238761 is a deficient number, since it is larger than the sum of its proper divisors (1).

398238761 is an equidigital number, since it uses as much as digits as its factorization.

398238761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 435456, while the sum is 47.

The square root of 398238761 is about 19955.9204498314. The cubic root of 398238761 is about 735.7232986575.

It can be divided in two parts, 39823 and 8761, that added together give a palindrome (48584).

The spelling of 398238761 in words is "three hundred ninety-eight million, two hundred thirty-eight thousand, seven hundred sixty-one".